1. Field of the Invention
This invention relates to cargo carrying vehicles and, more particularly, to a cargo carrying vehicle that has an electrical component thereon that is capable of being operated using an external power source.
2. Background Art
It is common to transport cargo in over-the-road vehicles within receptacles with air therein that is cooled or otherwise conditioned to preserve the particular cargo. A cooling component, such as an air conditioning system, is typically run on 120 volts AC. The vehicle will have its own generator to supply the required power to the air conditioning unit and/or to any other component that is electrically powered.
Electrical power is required to operate these components in all sizes of vehicles. Most commonly, air treatment components are used in larger vehicles, such as semi-trailer trucks. Semi-trailer trucks typically have diesel engines that are used both to drive the vehicle and cause the generation of power supplied to the electrically driven components.
In the process of transporting cargo, semi-trailer trucks will often be parked by their operators, potentially for relatively lengthy periods. As an example, an operator may stop for a rest period of several hours. At an unloading terminal or location, the vehicle may be required to be parked for a significant time period before the cargo therein can be unloaded.
To avoid damage to, or perishing of, cargo contained within the vehicle, it is common to continuously operate the particular air conditioning components while the vehicle is “parked”. To do so, the truck engine will be operated in an “idle” mode.
While idling a diesel engine minimizes fuel consumption, there still results therefrom a significant emission of pollutants into the air, which represents a significant environmental hazard. These emissions are significant enough that many states have introduced regulations that restrict operation of the engines in the idle mode as for purposes of powering electrical components that must be continuously operated.
This has led to the proliferation of “shore power” stations. Particularly in regulated states, at locations where semi-trailer trucks are regularly parked, provision is made to supply 120 volt AC power to these vehicles.
Many existing cargo carrying vehicles are already equipped with an external supply inlet through which power can be tapped at these supply stations. Typically, a length of cable will be provided at the station with an end thereof equipped with a releasable connector that can be engaged with a cooperating connector on the vehicle. The vehicle operator, or an attendant, can relatively quickly establish the connection and initiate the power supply that continues through the parking period. This allows the operator to shut down the vehicle engine.
When the operator is ready to depart the station, the operator, or an attendant, will turn off the external power supply and disconnect the supply cable end from the vehicle. Power to the electrical components can then be re-supplied by the vehicle's own generator.
Vehicle operators have routinely used shore power at terminal locations. However, the en route conversion to shore power is a concept that is relatively new. As a result, an operator may forget that his/her vehicle is connected to shore power and depart from a parking location without disconnecting the power supply lead. This could have significant economic, and potentially dangerous, consequences.
One possible outcome is that the cable lead will be snapped or the connector components damaged or destroyed as the vehicle separates from the station. Depending upon the nature of the connection, the vehicle itself might be damaged and/or a significant component at the shore power station may be damaged or destroyed.
Aside from necessitating repairs, rupturing of high voltage lines under a tensile force inherently represents a safety risk to individuals in the vicinity of the station.
Still further, a rupturing of the line or damaging of the connections may cause shorting that could damage a powered component on the vehicle. This may necessitate immediate repairs that may not be practical or possible. As a result, the operator risks the loss of potentially an entire cargo.
To date, the effective and safe use of shore power has relied upon the operator's appropriate connection and disconnection of the shore power. However, a simple lapse in memory or judgment could have significant consequences. The industry continues to rely primarily upon the judgment and performance of vehicle operators to avoid such situations.